A robust and efficient technique to segment shaded areas in aerial color images is presented in this paper. This technique is based on the physical phenomenon of atmospheric dispersion of the sunlight most well known as the Rayleigh scattering effect. This technique does not depend on special algorithms to classify or to form clusters of objects appearing in complex aerial images. In fact, the mathematical model, derived from the physical model is very simple but it produces consistent results and can be applied to color images obtained by airborne and orbital sensors (e.g., Landsat TM and, IKONOS).